One piece molded spool



June 27, 1961 G. e. TUCKER, JR

ONE PIECE MOLDED SPOOL 2 Sheets-$heet 1 Filed June 18, 1958 IIIIIIIIIIIIII $4M fitter/3,398.

June 27, 1961 G. G. TUCKER, JR 2,990,133 our: PIECE MOLDED SPOOL Filed June 18, 1958 2 Sheets-Sheet 2 1/2 l/el? tor-.- Geolrge G. Tucke 3 fittarmgy.

United States Patent 2,990,133 ONE PIECE MOLDED SPOOL George G. Tucker, Jr., Auburn, Ind., assignor to American Pulley Co., Garrett, Ind., a corporation of Pennsylvania Filed June 18, 1958, Ser. No. 742,839 3 Claims. (Cl. 242-1185) This invention relates to spools of the type used for shipping and dispensing wire, and more particularly to a one piece molded spool.

Spools are employed in the wire industry for initially accommodating the wire as it comes from the wire insulating apparatus (or in the case of bare wire from the drawing or stranding equipment), the wire being stored, shipped to the wire user, and ultimately dispensed from the same spool. Spools for use with relatively small diameter wire, such as enameled magnet wire used in the manufacture of such apparatus as motors and transformers, have in recent years conventionally been formed of metal; such spools when empty have generally been returned by the wire user to the wire manufacturer for reuse. Since the return of empty spools involves subst a ntial expense in handling and shipping, it has for some time been felt desirable to provide a wire spool which could be manufactured and sold at a sufficiently low cost to permit its being thrown away after one use.

The provision of a molded plastic wire spool immediately suggests itself as a solution to the requirement for a throw-away spool. However, a wire spool must satisfy several quite rigid structural requirements. For instance, the barrel portion of the spool must have suficient strength not only to support the weight of the wire wound thereon, but more particularly, to withstand the force exerted thereon during the winding operation. Furthermore, considerable side-wise force is exerted on the'endflanges or heads of the spool by the traversing apparatus which guides the wire alternately from one side to the other as it is wound on the spool, the accumulation of a number of layers of wire further having a tendency to spill over at the sides, thus exerting further sidewise force on the heads. More particularly, however, spools filled with wire are generally stored with their heads resting on a flat surface and may be stackedone upon the other to a considerable height. This means that the filled spool is lifted by one head so that the entire weight of the wire (which in the case of a typical sixinch wire spool filled with enameled copper wire, may be on the order of ten pounds) is in effect suspended from the head being lifted. It is thus particularly necessary that the head portions of the spool be sufficiently strong to withstand not only side-wise force due to traversing and spill over tendency of the wire, but also lifting; it will be seen that deflection of the head portions further tends to collapse the barrel portion of the spool. There is a further requirement that the arbor tube portion of the spool be sufliciently rigidly secured to the barrel portion so as to prevent relative axial movement of the barrel and arbor tube portions.

In considering the design of a molded plastic wire spool, it is evident that a one piece, i.e., unitary construction, is desirable; the cementing together of two spool sections introduces a number of problems which tend to increase the overall cost of the spool, not the least of which is the additional operation required to join the two sections. A number of one piece molded plastic wire spools are known to the applicant, however, in order to fulfill the above set forth strength requirements, such spools have required the use of so much molding matethat the material cost has effectively precluded their e a t row-aw y spo ls- It is therefore a general ob ect of my invention to provide an improved molded spool.

Another object of my invention is to provide an improved molded spool particularly suited for use as a wire spool which can be produced at a sufliciently low cost to permit its being thrown away after one use.

A further object of my invention is to provide ,an improved one piece molded plastic wire spool which possesses the requisite strength yet employs less molding material than prior one piece molded plastic wire spools known to the applicant.

A still further object of my invention is to provide an improved one piece molded plastic wire spool which employs the least possible molding material yet nevertheless provides the requisite structural strength.

Yet another object of my invention is to provide an improved molded spool having the desirable features enumerated above.

Further objects and advantages of my invention will become apparent by reference to the following description and the accompanying drawings, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

My invention, in one aspect thereof, provides a one piece molded spool having a tubular barrel portion with the other spider portion. In the preferred embodiment of my invention, each of the spokes of the two spider portions has a pair of flanges respectively formed on its sides extending radially between the arbor tube portion and the barrel portion and axially toward the other spider portion thereby preventing relative axial movement of the arbor tube portion and the barrel portion, and the head portions are respectively spaced from the ends of the barrel portion and have a plurality of radially extending ribs for-med on their outer faces thereby preventing deflection due to traversing and lifting forces.

In the drawings.

FIG. 1 is a view in perspective, partly broken away, illustrating my improved one piece molded plastic wire spool;

FIG. 2 is a cross-sectional view taken along the line 22;

FIG. 3 is an end view of my improved molded spool;

FIG. 4 is a fragmentary cross-sectional view further illustrating the preferred configuration of the head portionsof the spool of FIG. 1;

FIG. 5 is a fragmentary view in perspective illustrating my improved one piece molded plastic wire spool with a modified form of insert to provide a surface upon which a label may be afiixed; and

FIG. 6 is a view in perspective modified form of insert of FIG. 5.

Referring now to FIGS. 1, 2 and my improved one piece molded plastic wire spool, generally identified as 1, comprises a relatively thin-wall tubular barrel portion 2. A pair of annular bead portions 3 and 4 extend outwardly from barrel portion 2 and are respectively spaced inwardly from its ends 5 and 6 as shown. The head portions 3 and 4 respectively have axially outwardly extending flange portions 7 and 8 formed at their outer peripheries and a plurality of evenly spaced rib portions 9 and 10 extend axially outwardly from the facesll and 12- of the head portions 3 and 4 of the spool of FIG. 1

further showing the 3 of the drawing,

18 respectively join the ends of arbor tube portion 16 to the ends of barrel 2, the spider portions respectively having pairs of spokes 19 and 20 and 21 and 22 as shown. The spokes 19, 20, and 21, 22 of the spider portions 17 and 18 are equally spaced apart with their side edges falling on radii from the axial center line 23 of the spool. 1 Furthermore, and with particular reference to FIG; 3, it will be observed that the angles defined by the sides of the spokes 21 and 22 are respectively equal and equal to the angular extent of the spaces 24- and 25 between the spokes 21 and 22. It will now further be observed that the spokes 19 and 20 of the spider member 17 are identical to the spokes 21 and 22 of the spider member 18, being, however, disposed at 90 with respect thereto so that spokes 19 and 20 axially coincide with spaces 24 and 25 between spokes 21 and 22. This displacement of the spokes 19 and 20 of the spider 17 with respect to the spokes 21 and 22 of the spider 18 permits the molding of the spool 1 in one piece, as will be hereinafter more fully described.

Each of the spokes 19 through 22 has a pair of relatively short flanges 26 and 27 formed on its sides extending radially between the outer surface of the arbor tube 16 and the inner surface of the barrel 2 and axially toward the other spider portion. The ribs 26 and 27 in cooperation with the respective spokes 19 through 22 provide in essence a channel-shaped structural member which prevents axial movement of the arbor tube 16 with respect to the barrel 2. Each of the spokes 19 through 22 further is provided with an elongated driving slot 28 which serves not only for engagement with a suitable driving dog on the winding apparatus for rotating the spool in order to take up the wire, but which also serves an additional function during the molding operation as will be hereinafter more fully described.

It will now be observed that the outer edges of the flanges 7 and 8, ribs 9 and 10, the ends and 6 of the barrel portion 2, the ends 29 and 39 of the arbor tube 16 and the outer faces of the spokes 19, 20 and 21, 22 respectively fall in generally the same planes which are each at right angles to the axial center line 23 of the spool 1 and its barrel and arbor tube portions 2 and 16. The outer faces of the spokes 19, 20 and 21, 22 are, however, preferably slightly recessed as at 38 to permit application of a label thereto. Alternatively, a thin annular disc 39, formed of suitable material, such as metal, may be provided at one end of the spool 1, preferably having a thickness no greater than the amount the spokes 21 and 22 are respectively recessed from the end 6 of barrel 2 and end 30 of arbor tube 16. Disc 39 preferably has an outside diameter slightly smaller than the inside diameter of barrel portion 2 and has a center opening 40 adapted to fit over the portion of arbor tube 16 which extends beyond spokes 21 and 22 respectively. Disc 39 may be held in assembled position abutting the outer faces of spokes 21 and 22 by means of resilient flange portions 41 which extend into the spaces 24 and 25 between the spokes 21 and 22 and resiliently engage the inner wall of barrel portion 2. An appropriate paper label may then be glued to the outer face of the disc 39. It will be readily seen that an identical disc 39 may, if desired, be snapped into position at the other end of the spool 1 abutting the outer faces of the spokes 19 and 20. It will now be seen that by virtue of the spacing of the head portions 3 and 4 inwardly from the ends 5 and 6 of the barrel 2 together with the provision of the radially extending ribs 9 and and the integral joining of the spokes 19 through 22 of the spiders 17 and 18 with the adjacent barrel extension portions 13 and 4 14 and ribs 9 and 10, the head portions 3 and 4 are effectively made exceedingly strong so that appreciable deflection due either to traversing or lifting is prevented.

Referring now to FIG. 4, which is an enlarged fragmentary cross-sectional view of the head portion 4, the outer edge of flange 8 preferably has a recessed portion 42 formed therein during the molding operation; it will be readialy apparent that a small flash is necessarily formed at the junction 43 of the outer face of flange 8 and its end, and the provision of the recess 42 moves this flash below the outer periphery of the flange so that wire coming off of the spool will not abrade on this flash. Referring now to FIGS. 5 and 6 in which like elements are indicated by like reference numerals, unitary molded plastic insert members 42 may be inserted in the spaces 24 and 25 intermediate the spokes 21 and 22 at one end of the spool again in order to provide a convenient surface in conjunction with the spokes 21 and 22 upon which a label may be affixed. Insert members 42 are shaped to conform respectively to the configuration of spaces 24 and 25 and each has a peripheral flange portion 43 and a web portion 44 which, in assembled position, has its outer surface flush with the outer surfaces of spokes 21 and 22. In order to retain the insert members 42 in position in the spaces 24 and 25 between spokes 21 and 22, each of the spokes may have suitable indentations 45 formed in its outer surface communicating with each edge thereof in which corresponding projections 46 formed on the edges of the insert members 42 are fitted. Furthermore, small interference tabs or projections 47 are preferably formed on the inner edges of the flange portion 43 of insert members 42 intermediate projections 46, tabs 47 snapping into engagement with the inner edges of flanges 26 and 27 of spokes 21 and 22 thereby to hold the insert members 42 in position. it will be readily understood that the insert members 42 may be provided in either or both of the openings 24 and 25 at one end of the spool and may additionally be provided to fill either or both of the openings 32 and 33 intermediate the spokes 19 and 20 at the other end of the spool. It will be readily seen that the insert members 42 may be molded in one piece from suitable plastic material and that identifying indicia of the spool or wire manufacturer may be molded on the outer surface of the web portion 44. Thus, insert members 42 having different indicia for different wire manufacturers may simply and inexpensively be provided in connection with the same basic one piece molded plastic spool of my invention.

In the molding of my improved spool 1, a conventional horizontally separable mold is preferably employed and it will be readily seen that two core portions extend inwardly in one direction while two other core portions extend inwardly in the other direction and are disposed between the first two core portions to form the bore of the barrel portion 2, the outer surface of the arbor tube portion 16, and the spokes 19 through 22 of the spider portions 17 and 18; after injection of the molding material into the mold and before the separation of the two halves and removal of the core portions, the two core portions extending in one direction extend through the spaces 24 and 25 between spokes 21 and 22 while the other two core portions extending in the opposite direction extend through the spaces 32 and 33 between the spokes 19 and 20. -It will further be seen that the ends of the core portions which extend through the spaces 24 and 25 form the flanges 26 and 27 on the spokes 19 and 20 while in turn, the ends of the core portions extending through the spaces 32 and 33 between the spokes 19 and 20 form the flanges 26 and 27 on the spokes 21 and 22. The four core portions which cooperate to form the bore of barrel 2, the outer surface of the arbor tube 16, and the spokes 19 through 22 with their associated flange portions 26 and 27 must necessarily be provided with a slight draft thus providing the draft lines 34 and 35 on the outer surface of the arbor tube 16 and the inner surface of the barrel 2 respectively, as shown. Guide pins on the ends of the core portions respectively form slots 28 in spokes 19 through 22. *In addition, the completed spool l'is ejected from the mold by suitable ejection pins, as is well known in the art, and in order to prevent these pins from perforating the still warm molded plastic material forming the, spokes 19 and 20, internal ribs 36 and 37 join the inner surface of the spokes 19 and 20 adjacent their outer peripheries to theinner surface of the barrel 2, as shown.

While in the spool shown in the drawing the spider portions 17 and 18 are shown as comprising two spokes respectively, it will be readily apparent that in any particular spool design, each spider portion may be formed of three or even more spokes, the only general requirement being that the spokes at onerend of the spool axially coincide with the spaces between the spokes at the other end of the spool. Furthermore, in the case of spools in the smaller sizes, the head portions 3 and 4 may have suflicient strength to permit elimination of some or all of the ribs 9 and 10, thereby providing a flat area to which a label may be aifixed or on which any desired indicia may be printed, stamped or embossed.

In an actual wire spool manufactured by the applicants assignee in accordance with this invention, head portions 3 and 4 had a diameter of six inches (the spool is thus referred to as a six-inch spool), and the barrel 2 had an overall length of four inches, an outside diameter of three and one-half inches, and a wall thickness of .078 inch. The arbor tube 16 had an inside diameter of .635 inch and a wall thickness of one-sixteenth inch and the head portions 3 and 4 had a thickness of .085 inch with their inner surfaces being spaced from the outer edges 5 and 6 of the barrel portion 2 by one-quarter of an inch, respectively, thus providing a winding space on the barrel 2 of three and one-half inches. The spoke portions, 19 through 22, of the spider portions 17 and 18 were respectively .085 inch thick with the flanges 26 and 27 being respectively one-quarter inch wide to the front surface of the spokes 19 through 22, the faces of the spokes 19, 20 and 21, 22 being recessed .015 inch from the ends 5 and 6 of the barrel portion 2 and 29 and 30 of the arbor tube portion 16. Each head 3 and 4 is provided with thirty equally spaced ribs, 9 and 10, respectively one-sixteenth inch wide and spaced on radii from the axial center line 23 twelve degrees apart. This spool was formed of black polystyrene and its completed weight was approximately 6.165 ounces. Since this spool will accommodate copper wire weighing ten pounds, and is capable of being lifted by its heads 3 and 4, it is readily apparent that my improved design provides exceptional strength for the extremely small weight of molding material involved.

While 'I have shown and described a specific embodiment of my invention, further modifications and improvements will occur to those skilled in the art, and I desire in the appended claims therefore to cover all modifications which do not depart from the spirit and scope of this invention.

What is claimed is:

1. A one piece integrally molded plastic spool for wire comprising: a thin-wall tubular barrel portion; a pair of annular thin-wall head portions extending radially outward from said barrel portion a substantial distance and respectively spaced inwardly from its ends, each of said head portions having a relatively short axially outwardly extending flange formed on its outer periphery and a plurality of radially extending thin-wall ribs formed on its outer face and extending between said flange and said barrel portion; a thin-wall arbor tube portion concentrically arranged within said barrel portion and axially coextensive therewith; a first spider portion joining one end of said barrel portion to one end of said arbor tube portion and having at least two evenly spaced apart thinwall spokes with their sides respectively on radii from the axial center line of said spool, said spokes being respectively equal in angular extent to the spaces therebetween; another spider portion joining the other end of said barrel portion to the other end of said arbor tube portion and having thin-wall spokes respectively axially coextensive with the spaces between the spokes of said first spider portion; each of said spokes having a pair of relatively short thin-wall flanges respectively formed on its sides extending radially between said arbor tube portion and said barrel portion and axially toward the other spider portion but substantially axially spaced from the flanges thereof; the axially outer edges of said head flange, ribs, barrel and arbor tube portion at each end of said spool lying in generally the same plane normal to the axis of said spool; the outer faces ofsaid spokes at each end of said spool being slightly recessed from the respective ends of said barrel and arbor tube portion; and a thin annular dischaving a thickness approximately equal to the amount the said outer faces of said spokes are recessed'from the respective ends of said barrel and arbor tube portion, said disc having an outside diameter smaller than the inside diameter of said barrel portion and having a center opening larger than the outside diameter of said arbor tube portion, said disc being arranged abutting the outer faces of the spokes of one of said spider portions with its center opening embracing said arbor tube portion, said disc having'portions extending inwardly in the spaces between the spokesof said one spider portion and resiliently engaging the inner wall of said barrel portion thereby removably retaining said disc in its assembled position.

2. A one piece integrally molded plastic spool for wire comprising: a thin-wall tubular barrel portion; a pair of annular thin-wall head portions extending radially outward from said barrel portion a substantial distance and respectively spaced inwardly from its ends, each of said head portions having a relatively short axially outwardly extending flange formed on its outer periphery and a plurality of radially extending thin-wall ribs formed on its outer face and extending between said flange and said barrel portion; a thin-wall arbor tube portion concentrically arranged within said barrel portion and axially coextensive therewith; a first spider portion joining one end of said barrel portion to one end of said arbor tube portion and having at least two evenly spaced apart thinwall spokes with their sides respectively on radii from the axial center line of said spool, said spokes being respectively equal in angular extent to the spaces therebetween; another spider portion joining the other end of said barrel portion to the other end of said arbor tube portion and having thin-wall spokes respectively axially coextensive with the spaces between the spokes of said first spider portion; each of said spokes having a pair of relatively short thin-wall flanges respectively formed on its sides extending radially between said arbor tube portion and said barrel portion and axially toward the other spider portion but subsantially axially spaced from the flanges thereof; the axially outer edges of said head flange, ribs, barrel and arbor tube portion at each end of said spool lying in generally the same plane normal to the axis of said spool; and at least one unitary molded plastic member inserted in the space intermediate to said spokes at one end of said spool and substantially filling the same, said insert member having its outer surface flush with the outer surface of said two spokes.

3. A one piece integrally molded plastic spool for wire comprising: a thin-wall tubular barrel portion; a pair of annular thin-wall head portions extending radially outward from said barrel portion a substantial distance and respectively spaced inwardly from its ends, each of said head portions having a relatively short axially outwardly extending flange formed on its outer periphery and a plurality of radially extending thin-wall ribs formed on its outer face and extending between said flange and said barrel portion; a thin-wall arbor tube portion concentrically arranged within said barrel portion and axially coextensive therewith; a first spider portion joining one end of said barrel portion to one end of said arbor tube portion and having at least two evenly spaced apart thinwall spokes with their sides respectively on radii from 7 the axial center line of said spool, said spokes being respectively equal in angular extent to the spaces therebetween; another spider portion joining the other end of said barrel portion to the other end of said arbor tube portion and having thin-wall spokes respectively axially coextensive with the spaces between the spokes of said first spider portion; each of said spokes having a pair of relatively short thin-wall flanges respectively formed on its sides extending radially between said arbor tube portion and said barrel portion and axially toward the other spider portion but substantially axially spaced from the flanges thereof; the axially outer edges of said head flange, ribs, barrel and arbor tube portion at each end of said spool lying in generally the same plane normal to the axis of said spool; and at least one unitary molded plastic member inserted in the space intermediate two of said spokes at one end of said spool and substantially filling the same, said insert member having its outer surface flush with the outer surface of said two spokes; said insert member having a peripheral flange portion engaging the respective flanges on said two spokes, the outer surface of said arbor tube portion intermediate said flanges on said two spokes and the inner surface of said barrel portion intermediate said flanges on said two spokes; each of said two spokes having at least one indentation formed in its outer surface communicating with its edge adjacent the said space in which said insert member is positioned, the corresponding edges of said insert member having projections formed thereon respectively seated in said indentations in said two spokes, said peripheral flange portion of said insert member having at least a pair of interference tabs formed thereon respectively engaging the inner edges of said flanges on said two spokes, thereby removably retaining said insert member in assembled relation.

References Cited in the file of this patent UNITED STATES PATENTS 2,693,323 Jarmicki Nov. 2, 1954 2,851,801 Jennings Sept. 16, 1958 FOREIGN PATENTS 663,764 Great Britain Dec. 27, 1951 705,314 Great Britain Mar. 10, 1954 706,442 Great Britain May 31, 1954 

